首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 54 毫秒
1.
由于自发地理信息数据主要来源于志愿者上传,不可避免地存在数据质量缺乏保障等问题,故限制了其广泛应用。针对自发地理信息数据质量未知、参考数据难以获取等问题,本文引入了数据可信度的概念,从区域内用户信誉度之和与数据变化趋势2个方面对自发地理信息的可信度进行评价,将定性分析结果进行量化表达。首先,利用李纳斯定理计算区域内用户的信誉度之和获取数据质量的相关信息,以志愿者上传数据中保留的点所占比重作为志愿者的信誉度,构建了基于点统计的志愿者信誉度模型。接着,从数据量变化的趋势中获取数据的质量信息,通过计算研究区域内数据量的变化程度进行数据变化趋势度量。最后,以北京等地区OpenStreetMap数据作为实验对象,验证了方法的有效性。实验结果表明,利用该方法所得出的实验结果与基于参考数据的质量评价结果总体上保持一致。  相似文献   

2.
自发地理信息概念的兴起使越来越多的人参与到地理信息数据生产中,目前相对成熟的平台为OpenStreetMap(OSM)。由于自发地理信息的数据贡献者来自各行各业,其数据质量的优劣成为研究者关注的问题。以河南省铁路网为研究对象,针对其数据的适用性,主要采用地理信息技术的相关手段,将国内应用范围较广的高德地图与OSM数据进行对比,使用Python语言与ArcPy站点包对数据进行批处理,结合总长度完整性、数据重叠度、空间分异率及相对位置精度等指标探究OSM数据的质量及适用性。实验结果表明,OSM在河南省内的铁路数据与高德地图具有较高的一致性,且存在更新速度快的优点,可以在日后的研究中广泛应用。  相似文献   

3.
随着计算机技术与互联网技术、卫星定位技术、移动终端技术的发展,地理信息服务的模式正在发生改变,志愿者地理信息时代悄然而来。文章以志愿者地理信息的产生为索引,从数据的采集、处理、管理和质量控制等方面就国内外志愿者地理信息的研究与应用情况进行了回顾,讨论了目前志愿者地理信息存在的问题与发展趋势。  相似文献   

4.
地理信息标准化的最新进展   总被引:5,自引:0,他引:5  
实现数据共享的关键问题主要有数据结构、数据模型和数据格式的统一;地理信息的标准化;空间数据质量;数据的互操作;网络建设;政策和法规。这些问题的解决,才能营造一个地理信息共享环境。其中地理信息标准化是地理数据共享的关键问题之一。本文主要介绍国内外地理信息标准研究的最新进展,并提出我国在研究和制定地理信息标准时应采取的对策。  相似文献   

5.
《地理信息世界》2007,5(2):39-39
地理信息是指与所研究对象的空间地理分布有关的信息,它表示地表物体及环境固有的数量、质量、分布特征、联系和规律。从地理实体到地理数据,再到地理信息的发展,反映了人类认识的巨大飞跃。地理信息属于空间信息,其位置的识别是与数据联系在一起的,它具有区  相似文献   

6.
地理国情普查和监测为基础地理信息的及时更新提供了持续、可靠的参考数据。本文针对地理国情普查监测成果应用和基础地理信息数据更新的实际需求,从数据转换、要素匹配、变化识别和增量更新等方面设计了基于地理国情数据的基础地理信息数据更新技术框架。针对要素相似性匹配和变化识别难题,从距离、面积和形状相似性等方面设计了面向几何要素匹配与变化识别的系列指标、算法和知识规则。研究成果在山东莱芜某地进行了应用。实验结果表明,本文设计的方法对变化要素的识别精度达96.6%,极大地提高了基础地理信息更新的工作效率。研究成果不仅为基础地理信息增量式更新提供了技术支撑,同时也将提高地理国情数据成果的应用价值。  相似文献   

7.
林业地理信息,是以森林资源及生态环境为研究对象,依托现代地球观测、大数据、物联网、云计算等先进技术,通过精准的时空观测,实施精准的时空作业,达到理想林业时空模式,从而使森林最大限度地发挥生态效益、社会效益和经济效益。林业地理信息主要应用在森林观测、森林经营、造林、森林灾害防控方面。本文从林业地理信息特征、林业地理信息产业需求和林业地理信息装备创新3个方面对林业地理信息进行阐述。  相似文献   

8.
<正>《地理信息世界》创刊于1994年,刊载地理信息理论研究、技术应用和产业政策等方面的研究成果和发展动态。创刊20多年来,《地理信息世界》作为以推动测绘地理信息学术创新、科技创新、产业创新为宗旨的,具有权威性的国内外公开发行的中国科技核心期刊,广泛交流学术成果,积极活跃学术氛围,办刊水平日益提升,在推动测绘地理信息成果应用、繁荣地理信息科技发展以及新技术推广、人才培养等方面发挥了重要作用。2016年底,国家测绘地理信息局决定,《地理信息世界》由国家基础地理信息中心、中国地理信息产业协会和黑龙江测绘地理信  相似文献   

9.
我国地理信息产业发展特征   总被引:7,自引:0,他引:7  
本文通过相关文献和数据收集,从政策、市场、企业、产品等方面,对我国地理信息产业发展现状与特征进行了简单综述。我国地理信息产业正处在诞生阶段,市场规模较小,但发展迅速,潜力巨大。在产业结构和区域布局上,地理信息产业发展不平衡。数据产业已成为产业发展的瓶颈,软件产业和地理信息集成服务极具发展潜力。从产业发展的主导因素看,政府在地理信息产业发展中起着关键作用;从产业发展的推动力来看,地理信息技术储备不足,亟待创新。  相似文献   

10.
地理信息生产的组织与质量管理,可分为宏观和微观两个层次.就目前来说,地理信息产业处在初创阶段,地理信息生产的内容包括:地理数据(空间数据和属性数据)的采集和录入,包括建库及建库前的各工序工作;  相似文献   

11.
12.
Based on the hydrographic data in austral summer during the 22nd Antarctic Expedition of China(2005/2006),some features can be found about the northern margin of Emery ice shelf as follows.The heat content in the surface layer(0-50 m) at the eastern end and the western end of the ice-shelf margin is much higher than that at the middle.The upper mixing-layer depth and the seasonal thermocline depth at the middle of the ice-shelf northern margin are much shallower than those at the both ends.However there is much less difference between the middle and the ends in the bottom layer.The remote sensing photos show that the inhomogeneity in the surface-layer water is closely related to the spatial distribution of the floes and polynia in the area.  相似文献   

13.
Phylogenetic analysis based on 16S rDNA of 8 strains of cultivable bacteria isolated from Arctic sea-ice was studied.The results showed that strain BJ1 belonged to genus Planococcus,which was a genus of low mole percent G C gram-positive bacteria;strain BJ6 belonged to genus Burkholderia of β-proteobacteria and the rest 6 strain all belonged to γ-proteobacteria,of which strain BJ8 was a species of Pseudoalteromonas,strain BJ2-BJ5 and BJ7 were members of genus Psychrobacter.Phylogenetic analysis also indicated that bacteria of genus Psychrobacter of the isolates formed a relatively independent phylogenetic cluster in comparison with other bacteria belonged to genus Psychrobacter.  相似文献   

14.
正1 Aims and Scope Advances in Polar Science(APS)is an international,peer-reviewed journal jointly sponsored by the Polar Research Institute of China and the Chinese Arctic and Antarctic Administration.APS is a comprchensive academic journal dedicated to presentation of multi-disciplinary achievements in Arctic and Antarctic expeditions and research.Its primary purpose is to publish achievements in fundamental research,applied  相似文献   

15.
16.
《山地科学学报》2014,(4):I0004-I0009
<正>AIMS AND SCOPE(Editorial Policy)The Journal of Mountain Science(JMS)is devoted to mountains and their surrounding lowlands-ecoregions of particular global importance,with a particular emphasis on the important highlands/mountains in the world,such as the Tibetan Plateau,the Himalayas,the Alps,the Andes,the Rockies and many other mountain ranges of our planet.  相似文献   

17.
<正>The Journal of Mountain Science(JMS),founded in2004,is an international English-language journal on mountain sciences.JMS is supervised by the Chinese Academy of Sciences(CAS),sponsored by the Chengdu Institute of Mountain Hazards and Environment,CAS,published by Science Press China,and distributed by Springer exclusively throughout the world(excluding Mainland China).The JMS is published bimonthly,fulltexted in SpringerLink and CNKI,indexed/abstracted by  相似文献   

18.
Using the NCEP/NCAR reanalysis monthly 500 hPa height data on a 2.5 latitude-longitude grid and 1°×1° sea ice data,the polar vortex area,intensity index and arctic sea ice area index are calculated respectively,and the meridional distribution,period variation and the abrupts in the long range trend are analyzed to study their relationship.The results show that the meridional distribution of sea ice and polar vortex h-ave distinctive difference,the relative positions of them are different in the eastern and western hemispheres,and exept they have periods of 4 months,quasi half year,quasi year,4-5 years and 10 years commonly,and each of them has its own respective variation as well.The sea ice area is decreasing apparently since 1980's,so is the polar vortex area,but their abrupt changge time are different totally.The area of sea ice and polar vortex has prominent positive correlation,but the relationship of sea ice intensity,polar vortex intensity,polar vortex area is complicated.  相似文献   

19.
The ability of cell to modulate the fluidity of plasma membrane was crucial to the survival of microorganism at low temperature. Plasma membrane proteins, fatty acids and carotenoids profiles of Antarctic psychrophilc yeast Rhodotorula sp. NJ298 were investigated at -3 ℃, 0 ℃ and 8 ℃. The results showed that plasma membrane protein content was greater at -3 ℃ than that at 8 ℃, and a unique membrane polypeptide composition with an apparent molecular mass of 94.7 kDa was newly synthesized with SDS-PAGE analysis; GC analysis showed that the main changes of fatty acids were the percentage of unsaturated fatty acids (C18∶ 1 and C18∶ 2) and shorter chain saturated fatty acid (C10∶ 0) increased along with the decrease of the culture temperature from 8 ℃ to -3 ℃; HPLC analysis indicated that astaxanthin was the major functional carotenoids of the plasma membrane, percentage of which increased from 54.6±1.5% at 8 ℃ to 81.9±2.1% at -3 ℃. However the fluidity of plasma membrane which was determined by measuring fluorescence anisotropy was similar at -3 ℃, 0 ℃ and 8 ℃. Hence these changes in plasma membrane's characteristics were involved in the cellular cold-adaptation by which NJ298 could maintain normal plasma membrane fluidity at near-freezing temperature.  相似文献   

20.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号